Knife-sharpener attachment



Dec, 1924. v 1,518J81 O. C. CRAVER KNIFE SHARPENER ATTACHMENT Filed July 1924 :1 mon tor Patented Dec. 9, 1924.

UNITED STATES OSCAR C. CRAVER, OF PHILADELPHIA, PENNSYLVANIA.

KNIFE-SHARPENER ATTACHMENT.

Application filediuly 18, 1924. Serial No. 728,700.-

To all whom it may concern:

Be it known that I, OSCAR C. CRAVER, a citizen of the United States, residing at supporting attachment adapted to provide satisfactorily for such sharpening action.

As shown in Fig. 4 this blade-supporting Philadelphia, in the county of Philadelphia attachment is simply formed from a piece and State of Pennsylvania, have invented of sheet metal bent to span a series of discs certain new and useful Improvements in Knife-Sharpener Attachments, of which the following is a specification.

My invention relates to sharpening devices, and particularly to that type which employs parallel series of overlapping discs to provide a determined edge contact of the transversely moved instrument, with the peripheral edges of the discs; and my improvement consists in an attachment whereby the blades of scissors for instance may be fixedly supported as desired during the sharpening movement thereof to insure the securing of a uniformly beveled edge,'.as fully described hereinafter in connection with the accompanying drawings and clearly defined in the subjoined claims.

Fig. 1 is a side elevation of a sharpener having my invention applied thereto inone operative position; Fig. 2 is a plan view of the same; and Fig. 3 is a similar view to Fig. 1 showing my attachment inv reverse position upon the same axle, and also indicating in dotted lines its like application to the axle of. the other series of discs. Fig. 41 is a separate view of my attachment in the preferredform indicated in Figs. 1 to 3.

The known type of knife sharpener in connection with which my invention is illustrated and to which it is specifically adapted is made up of two similar series of sharpening discs; each series comprising discs, a a a or a a a, which are loosely mounted with separating washers b b b, on an axle, c or 0', extending between the spaced uprights d d of a suitable frame D. The parallel axles 0 0 are closed together to cause the edge portions of the discs to overlap and form an acute angled V-shaped intersection of the peripheries of the opposed discs, so that when a knife is drawn across the contacting peripheries of the discs, it is readily sharpened with a slight beveling relative to each face of the blade.

Such sharpening action however is not adapted for shearing instruments in which the cutting edge is formed in the plane of one face of the blade with a single bevel extending to the other face; and the object of my invention is to provide a simple blade? and provided with approximately parallel pivot members 1, 1 each of which is apertured as indicated at 2, 2 to pivotally engage one of the disc axles 0 or 0' within the respective frame uprights d d the connectlng plate 3 overhanging the discs and forming an inclined blade supform beveling action of the other series ofdiscs as the blade is drawn crosswise of the latter.

The angle of the uniform *bevel thus insured, to the face of the blade which is supportedupon the plate 3, is positively determined by the projection of the disc-contactin edge of the latter beyond a rightangle line 6. extending from the center of the disc axle on which the attachment is pivoted; and provision is made for varying this angle by merely reversing the position of the attachment on said axle as indicated in Fig. 3,-the plate edges 3 and 3 being differently spaced from said line 6 so that the angle of contact with the opposed discs will be correspondingly different. The attachment may also be applied to either disc axle as indicated by the dotted showing in Fig. 3, so that one or other. of the two series of discs may be used to effect the sharpenmg.

It will be understood that the discs may be employed in the usual manner for sharpening knives, by swinging the attachment out of the way or removing it; while scissors blades or the like may be just as readily sharpened with a single bevel of desired uniform angle, by merely throwing the attachment into service as a fixed support for one face of the blade.

What I claim is:

1. In om ination with a Sharpener comprising two series of overlap ing discs loosely mounted upon parallel ax es; a supporting device arranged to span a series of discs with parallel pivot members thereof mounted upon the corresponding axle, and a connecting plate between said members either edge of which is adapted to contact with the peripheral edges of the opposed series of discs; the opposite contact edges of the connecting plate being difi'erently projected so as to provide difi'erent contact angles, said device being reversely mountable and adapted to thereby vary the contact angle.

2. In combination with a sharpener comprising two series of overlapping discs loosely mounted upon parallel axles; a. supporting device arranged to rcversably span one of said series of discs and having parallel pivot members adapted to pivotally engage the corresponding axle and a oonnectin plate between said members either edge 0 which is adapted to contact with the fperipheral edges of the opposed series 0 discs;

the oplposite contact ed es of said plate be1ng iflerently projected so that the plane of said late may form difi'erent contact angles WlGIl the device is reversely positloned upon the same axle.

2 3. In combination with a sharpener c0m r1s1ng two series of overlapping discs oosely mounted upon parallel axles a supporting device arranged to reverse y span one of said series of discs and having arallel pivot members. adapted to pivotal y engage the corresponding axle and a connecting plate between said members one edge of wh1ch is adapted to contact with the peripheral edges of the opposed series of discs; the plane of said connectin plate being approximately at right ang es to the planes of said pivot members and the opposite contact edges thereof being differently projected so as to provide different contact an les.

11 testimony whereof 'I afiix my signature.

OSCAR C. ORAVER. 

